Selecting system



J. H. BELL Nov. 24 1925.

SELECTING SYSTEM 7 Filed Feb. 12 1917 Patented Nov. 24, 1925.

UNTED STATES OFFICE.

JOHN H. BELL, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

SELECTING SYSTEM.

Application filed February To all whom it may concern: Be it known that 1, JOHN H. BELL, a subject of the King of Great Britain, residing at East Orange, in the county of Essex and State of New Jersey, have invented certain new anduseful Improvement-s inSelecting Systems, of which the following isa full, clear, concise, and exact'description.

This invention relates to selecting systems of an electromechanical type particularly adapted for use in printing telegraphy where tape transmission is employed.

The principal Object of this invention is to provide a two-way simplex system, eliminating the need of duplex balance which is diiiicult to maintain on aerial circuits during variable Weather conditions.

Another object is the provision of' means for correcting for line lag Without orientation to the distributors.

A further object is the provision of means for operating both distributors substantially in unison, without employing synchronizing apparatus.

' For the accomplishment of the above objects the invention contemplates the use of a rotary distributor at each station, arranged I to cooperate with a current controller or automatic tape transmitter to form current,

impulses for the line, and to cooperate with a selecting mechanism to distribute the effects of current impulses from over the line. In combination with the above appara'ltus, means are provided for causing said distributors to alternately associate the line with the current controller and selecting mechanism whereby each station alternately acts as a receiver-and transmitter.

The above and other objects of this invention will be fully set forth in the following.

description and claims, and will be more readily understood by reference to the-accompanying drawing which discloses a specilic embodiment, particularly adapted for use in printing telegraphs.

The system is an improvement on the system disclosed and claimed in a copending application, Serial No. 147,800, filed February 10, 1917, issued as Patent No. 1,303,496, May 13, 1911), and is preferably operated by the well-known Baudot code of various combinationsof live positive and negative impulses, except that an additional pulse is required for operating a release magnet, although other codes may be employed 12, 1917. Serial No. 148,113.

without departing from the spirit of thisinvention. The system has the advantageous feature that the same apparatus, may be utilized for transmitting and receiving selecting current impulses. The apparatus at substation A is precisely the same, and functions in precisely the same manner as the apparatus at station B. Therefore, only so much of the apparatus'will be described as is essential to a clear understanding of the system, and it will be understood that the description of apparatus at either station applies equally well to the corresponding apparatus at the other station.

In the following description it will be as-' sumed that station A is transmitting and station B receiving, although it is obvious that either station may be used for transmitting or receiving. Two stations, A and 1B, are shown interconnected-by a transmission line L. There may be as many stations as desired, but since they will all be similar to stations A, and B, there is no necessity for showing more. Preferably at each station, as shown at station A, there is a controller for selectively influencing the flow of current over the line L. This controller consists of a plurality of movable contact switches 15, 16, 17, 18 and 19, each of which is permanently connected to one of the segments 20, 21, 22, 23 and 24; respectively of the distributor 50. These movable contacts normally rest against fixed contacts which are connected to negative battery, but are I adapted to be moved into engagement with fixed contacts which are connected to positive battery. Movable contacts 15 to 19 inclusive are selectively actuated by any of the well-known means, as for example, a plurality of character keys arranged in the form of an ordinary typewriter keyboard but preferably by an automatic actuator controlled by a perforated tape or the like.

The distributor arm 10 is frictionally mounted on ashaft 11 which rotates constantly in the direction of the arrow, and may be driven by a motor or any suitable driving mechanism. The arm 10 is arranged to be held from rotating, and to be stopped once during each revolution by a pawl 12 controlled by the electromagnet 13.

A better understanding of the system can be obtained from the description of the selection of a specific character and the various operations which take nlace in transmitting and receiving the necessary impulses for representing a given character. Assume that the system as shown is in ooeration, and that distributor arm 110 has made half a. revolution, and that the distributor arm 10 is still held by the pawl 12. Assume also, for example, that impulses for effecting the selection of the letter F- are to be sent from station A to station B, and that the character of the impulses required is positive, negative, positive, positive, negative. The depression of the F key of the keyboard or the passage of a tape through an automatic transmitter ,with perforations therein representingv the character F will transfer the movable contact switches 15, 17 and 18 from negative to positive battery, and thereby connect positive battery to distributor segments 20, 22 and 23, respectively. Brush 135 carried by distributor arm 110 now interconnects the two local seg ments 136 and 137 of the distributor 150, thereby establishing an energizing circuit for the release locking magnet 140. Magnet 1.40 pulls up its armature 141, but does not affect .any apparatus at this time. Brush 138 carried by arm 110 interconnects segment 131 with the sending portion of the common ring 139, which ring is divided into two sections, one for receiving and one for sending. While brush 138 rests on segment 131, a circuit is completed from grounded battery 142, segment 131, brush138', ring 139, line L, common ring 39, brush 38, segment 25, conductor 43, key 48 and contact thereof, through the energizing winding of neutral relay 44 to ground. Relay 44 thereupon attracts its armatures 45, 46 and 47. The attraction of the armature 45 establishes an energizing circuit for the release magnet 13 from grounded battery 49, armature 45, conductor 51 and winding of magnet 13 to ground. Magnet 13 attracts the pawl 12 and releases the distributor arm 10. The attraction of armature 46 establishes a holding circuit for relay 44 from grounded battery 49, locking winding of relay 44, armature 46, conductor 52, and

armature 41 of release locking magnet 40 to ground. Armature 47 in pulling up,

' provides ground for the polar line relay 54,

so that impluses may be .received over the line from station B, and the effects of these impulses distributed to the selecting mechanism at station A.

The distributor arm 10 has now been released, and it starts to rotate approximately one-half a revolution behind distributor arm 110. As brush 38 of distributor arm 10 passes over segments 26, 27, 28, etc, brush 138 of distributor arm 110 passes rver segments 120, 121, 122, etc., respectivtly, until arm 110 engages pawl 112 of release magnet 113, whereupon it is arrested until brush 38 of distributor arm 10 arrives upon segment 31 and ring 39. The moment the brush 38 interconnects segment 31 with ring .39, current flows from battery 42, segment 31, brush 38, ring 39, line L, ring 139, brush 138, segment 125, conductor 143, key 148 and contact thereof, through the energizing winding of neutral relay 144 to ground. Relay 144 thereupon attracts its armatures 145, 146 and 147. The attraction of armature 145 establishes an energizing circuit for release magnet 113 from grounded battery 149, armature 145, conductor 151, through the winding of magnet 113 to ground. Magnet 113 attracts pawl 112 and releases the distributor arm 110. The attraction of armature 146 completes a holding circuit for relay 144 from battery 149, winding of relay 144, armature 146, conductor 152, armature 141 of release locking magnet 140 to ground. Armature 147 pulls up and provides ground for polar line relay 154.

At the same time brush 3S interconnects segment 31 and ring 39, brush 35 interconnects local segments 36 and 37, thereby establishing an energizing circuit for release locking magnet 40 from grounded battery 55, winding of magnet 40, segment 36, brush 35 and segment 37 to ground. ,Mag net 40 pulls up its armature 41, thereby opening the holding circuit for relay 44, and armatures 45, 46 and 47 thereof fall back. When armature 45 falls back, release magnet 13 is deenergized, thereby permitting pawl 12 under the influence of spring 56 to move into the path of the distributor arm 10. Armature 46 in falling back does not afi'ect any apparatus, but simply creates another break in the holding circuit of the neutral relay 44. Armature 47, in falling back, removes the ground connectionfrom line relay 54, so that it will not be influenced by impulses sent over the line from station A. Brush 38 is now ready to pass over segments 20, 21, 22, 23 and 24, and

send to the line the selection set up by the current controller for selecting the character F, and the brush 138 is ready to pass over segments 126, 127, 128, 129fand 130 respectively, and distributes to the selecting mechanism 160 the effects of the impulses sent out from station A.

Recalling that movable contact switches 15, 17 and 18 of the current controller have been actuated to connect positive battery to sending segments 20, 22 and 23, and that movable contact switches 16 and 19 connect negative battery to sending segments 21 and 24, then, as brush 38 passes over segment 20, a positive pulse will be sent to line which will cause the line relay 154 to move its armature 157 into engagement with contact 158, thereby connecting positive battery 159 through armature 157, contact 158, to the receiving portion of ring 139. Now, as brush 38 travels over segment 20, brush 138 travels over segment 126, and thereby extends the circuit from battery 159, through I the winding of selecting magnet 161 to ground. Selecting magnet 161 will be operated to move a disc, or perform some function in connection with recording the character which is being selected. Now, since the second pulse is' of negative polarity, the brush 38, in traveling over segment 21, will send a negative impulse to the line which will not aifect the actuation of line relay 154 as this relay is biased to hold its armature 157 against the dead contact, and responds only to impulses of positive polarity. Consequently selecting magnet 162 will not be influenced when brush 138 travels over segment 127. The third and fourth impulses being of positive polarity, will effect the actuation of the line relay 154, as brush 38 W I passes over segments 22 and 23, in the same circuit for neutral relay 44 which pu manner as the first positive im ulse effected the actuation of thlsrelay. onsequently, selecting magnets 163 and 164 will likewise be actuated. Since the fifth pulse is of negative polarity, the line relay 154 and selecting magnet 165 will not be actuated.

The distributor 50 cooperating with the current controller has now impressed upon the line a series of selecting impulses, and the distributor 150, cooperating with the selecting mechanism, 160 and the line relay 154 has distributed the effects of these impulses to efl'ect the printing or recording of the selected character. The distributor arm 10 is now in engagement with its holding pawl 12, and the brush 138 of distributor arm 110 is interconnecting segment 131 and ring 139, thereby completing an energizing ls up and establishes an energizing circuit for re-. lease magnet 13, and causes therelease'of distributor arm 10. The two distributors when once set in operation will continue to" operate in this manner until switch 48 at station A or switch 148 at station B is actuated, to open the energizing circuit for relay 44 or relay 144, whereupon both distributor arms will come to rest against their respective holding pawls. In order to stop the distributors from rotating, it is only necessary to open switch 48 or switch 148 momentarily. VVhe-n both distributor arms are-.at rest against their respective holding pawls, they may be released or set in motion from either station by closing switchat station A or switch 170 at station B. Assume that it is desired to start the distributors from station A. Switch 70 is closed, thereby completing an energizing circuit for magnet 13 from grounded battery 49, switch 70, conductor 51 and the winding of magnet 13 to ground. Magnet 13 attracts the pawl 12 and releases the distributor arm 10 which is carried around by the constantly rotating shaft 11. As soon as brush 38 carried by the arm 10 interconnects the segment 31 with the common ring 35), a circuit is completed from grounded battery 42, through the energizing winding of neutral relay 144, which pulls up its armatures and establishes an energizing circuit for release magnet 113. Magnet 113 withdraws the holding pawl .112 'trom the distributor arm 110, and permits the latter to start to rotate approximately 180 behind the distributor arm 10.

It willreadily be seen that either station A or B may act as a transmitting station, a

receiving station or. as a combined transmitting and receiving station. It will also be seen that any number of stations may be interconnected by the line L, and while one station is transmitting all other stations may be receiving, which is a very essential feature in news distribution.

What is claimed is:

1. A selecting system comprising a pmralit of stations interconnected by a transmission line, an intermittently rotating current distributor at each of said stations, each of said distributors comprising a receiving and a sendin part, and automatic means associated 'Wltll said distributors whereby each may alternately act to receive and to transmit.

2. A selecting system comprising a plurality of stations interconnected by a transmission line, a periodically rotating current distributor at each of said stations, onehalf of each distributor being adapted for receiving and the other half for transmitting, and automatic means associated with each of saiddistributors whereby each distributor may receive and transmit during each revolution.

3. A selecting system comprisng a plurality of stations interconnected by a transmission line, independently driven rotary distributors at each of said stations, current control means cooperating with one of said distributors to produce current impulses over the line and selecting mechanism cooperating with the other o-f said distributors to distribute the effects of the current impulses irom over the line, and means independent of said current controller including a relay associated with each distributor and under the joint control of both distributors for releasing and stopping the rotation of the distributors.

4. A printing telegraph system comprising a plurality of stations interconnected by a transmission line, a rotary current distributor at each of said stations, a current controller cooperating with each of said distributors to produce code combinations of impulses over the line, a selecting mechanism cooperating with each of said distributors to distribute the effects of current impulses from over the line, and switching means at each station comprising a plurality of independently operable relays for controlling the rotation of said distributors.

5. In a selecting system an intermittently operating rotary distributor, means to set said distributor into operation, a circuit for said means, a plurality of devices for closing said circuit one of which is operated automatically by the distributor, and means rendered operative by rotation of the distributor for influencing the first mentioned means to arrest the operation of the distributor.

6. In a selecting system a distributor normally tending to rotate, means for controlling the rotation of said distributor, a circuit therefor, means for automatically closing tht circuit to release the distributor when at rest, and means responsive to the distributor when in operation for stopping the-rotation of the distributor through the instrumentality of the said automatic circuit closing means.

7. In a selecting system a sending distributor normally tending to rotate, an electroresponsive device for controlling the rotation 'of said distributor, a circuit therefor, means for closing said circuit to initiate the operation of said distributor, means controlled by the distributor for stopping the rotation thereof, and means for automatically closing the circuit of the electroresponsive device to again set the distributor in operation.

8. In a selecting system, a transmitting station and a receiving station, a transmission line connecting said stations, means at said transmitting station to transmit a starting impulse. followed by a group of selecting impulses over said line to the receiving station, an intermittently operating distributor at the receiving station, electromechanism at the receiving station to set the distributor in operation, and a relay for controlling said electro-mechainism, said re I lay being provided with a plurality of wind ings, one of said windings being traversed by a starting impulse received from said transmitting station for energizing said relay and another of said windings being.

provided for locking said relay in its actuated position.

9. In a selecting system, a distributor for transmitting impulses in groups comprising a series of segments, one of said segments controlling the transmission of a starting impulse and others of said segments controlling the transmission of selecting impulses, a receiving distributor, means at the receiving station responsive only to the starting impulse transmitted from the transmitting station, a magnet controlled by said means for initiating the operation of the receiving distributor, selecting mechanism associated with the receiving distributor and responsive to the selecting impulses, and

means rendered operative by the receiving distributor while in motion for arresting the operation of the said distributor through the instrumentality of said first'mentioned means.

10. In a telegraph system, a rotary transmitting distributor, a transmission line, selector switch mechanism cooperating with said transmitting distributor to send combinations of selecting impulses to said line, a receiving distributor connected to said line and tending normally to rotate, a detent for holding said receiving distributor against rotation, a magnet for actuating said detent, a relay under the control of the transmitting distributor and responsive to a starting impulse for effecting the en ergization of said magnet immediately prior to the transmission of a set of selecting impulses, an electromagnet, and switch contacts associated with said receiving distributor and adapted to be closed thereby for rendering said detent effective through the instrumentality of said electromagnet to arrest the movement of said receiving distributor after the receipt of said set of selecting impulsesl 11. The improvement in the method of operating a telegraph system in which distributors rotating in one direction only,

provided with transmitting .and receiving sections, are used at each oftwo different stations for automatically transmitting messages alternately in both directions, which consists in alternately starting the distributors in receiving positions in response to electric impulses coming through the others when the latter are in transmitting positions.

12. In a telegraph system, two stations each comprising a rotating distributor each provided with a plurality of transmitting and receiving contacts, a transmitter for transmitting groups of electric impulses through said transmitting contacts and a receiver comprising a plurality of electroresponsive devices. local circuit at each station including the electro-responsive devices and the receiving contacts of its distributor, and means for alternately arresting the rotation of each distributor and starti n 'the same in response to an electric impu lse passing through the other distributor, thereby causing the brushes of the transmitting distributor to pass over the transmitting contacts while those of the receiving distributor are passing over the receiving contacts.

13. In a telegraph system, transmitting and receiving devices located at each station, a line wire connecting the stations, a undircctional rotary distributor at each station for closing the line circuit through the transmitting devices and the receiving de-' vices at each statit-n in succession, and autoconnecting 1,5eaoo7 8 matic means for arresting the operation of said distributor after each operation "of the transmitting device whereby each station may alternately transmit and receive.

1-4. In a telegraph system, a transmitting device at each station for transmitting electric impulses over the line, and a receiving device at each station atfected by electric impulses passing over the line, a line wire the stations, and automatic means comprising a distributor rotating in one direction only at each station for alternately closing the line circuit through the transmitting device at one station and the receiving device of the other, and through the receiving device of the first station and the transmitting device of the other whereby each station may alternately transmit and receive.

15. In a telegraph system, a line wire connecting two stations, automatically operable means for alternately transmitting and receiving information between the two stations in opposite directions comprising a undirectional rotary distributor having a commutator provided with transmitting and receiving sections, means for arresting the rotation of the brushes after each operation of the transmitting device at the corresponding station, and means controlled by the distant station for starting the rotation of said brushes.

16. In a telegraph system, a distributor at each station, comprising a brush and a commutator provided with transmitting and receiving contacts, means for stopping each tit distributor at each revolution, and auto- .matic means for alternately starting each distributor in response to an electric impulse passing through the other when the starting distributor is in position to cause its brushes to engage its receiving contacts and at the time the brush of the other distributor engages its transmitting contacts whereby each station may alternately transmit and receive.

17. In a telegraph system, a device for transmitting electric impulses and a device for receiving electric impulses at each station, a line wire connecting the stations,

automatic means for alternately closing-theline circuit through the transmitting and rece ving devices of a given stationfiflsaid transmitting device comprising means for impressing a clearing impulse on a local.

the operation of said automatic means after each operation of the transmitting device, and means controlled from the distant station for starting said automatic means.

i 18. In a telegraph system, a device for transmitting electric impulses and a device for receiving electric impulses at each station, a line wire connecting the stations, automatic means for alternately closing the line circuit through the transmitting and receiving devices of a given station, said transmitting device comprising means for sending a clearing impulse, a starting impulseand a group of message impulses in succession, means for alternately arresting the operation of said automatic means at twostations after each operation of its transmitting device, and means controlled from the distant station for alternately starting said automatic means.

19. In a telegraph system, transmitting and receiving devices at each station, a line wire connecting the stations, a rotating distributor at each station having transmitting and receiving sections for alternately closing the line circuit through the transmitting and the receiving devices at each station and the corresponding sections of the distributor, means tendingto rotate said distributor continuously, means for arresting the rotation of the distributor after each operation of the transmitting device, and means controlled by the distant station for starting the distributorivhereby said stations operate automatically to' transmit and receive in alternation,

20. In a telegraph system, transmitting and receiving devices at each station, a line wire connecting the stations, a rotating distributor ateach station having transmitting and receiving sections for alternately closing the line circuit through the transmitting and the receiving devices at each station and the corresponding sections of the distributor, a continuously rotating motor connected to rotate said distributor, a friction connection interposed between said motor and said distributor, means for arresting the rotation of the distributor after each operation of the transmitting device, and means controlled by the distant station for.

starting the distributor whereby said sta- JUHN i. i BELL.

lot 

